More particularly, the invention relates to such irrigation systems known by the terms "point irrigation", "localized irrigation", or "drop by drop irrigation", whereby water is brought to the desired utilization point(s) in very small quantities so as to obtain optimum moistness with minimum water consumption. The apparatus used for this purpose are generally both complex in structure and thus expensive, and highly specific in the use to which they can be put because the water dispensing orifices are generally at a fixed spacing.
To obviate these drawbacks, French patent application FR-81 07317, filed Apr. 9, 1981, discloses apparatus comprising a main feed pipe made of elastically deformable material and a series of branches suitable for being connected merely by being forced into any point along at least one longitudinal portion of the main pipe which has a specially adapted cross-section such that when a branch is removed, the resilient compression forces in the substance from which the main pipe is made seal the passage which was opened by penetration of the branch.
Although this apparatus does indeed give satisfaction, its use requires the ends of the branches that are connected to the main pipe to be constituted by metal needles. This can sometimes lead to the apparatus leaking while in use where the branches are inserted because the metal needles heat up (particularly during periods of drought when these apparatuses are most used), thereby deteriorating the resilience of the substance from which the main pipe is made in the vicinity of the perforations, in particular when said substance is an elastomer of the rubber type.
A general object of the invention is to provide irrigation apparatus of the above-mentioned type which mitigates the drawbacks of known devices and in particular in which water-tightness is not degraded during successive periods of use.